Railroad crossing gate apparatus



Nov. 7, 1933. J. w. JENKINS 1,934,429

RAILROAD CROSSING GAT; APPARATUS Filed April 14, 195ol 6 Sheets-Sheet 1Nov. 7, 1933. J, w. JENKINS RAILROAD CROSSING GATE APPARATUS 6Sheets-Sheet 2 Filed April 14, 1930 NUV- 7, 193'n .1 w. JENKINS RAILROADCROSSING GATE APPARATUS Filed April 14, 1930 6 Sheets-Sheet 5 NOV. 7,y1933. w, JENKlNS 1,934,429

RAILROAD CROSSING GATE APPARATUS Filed April 14, 19.30 6 Sheets-Sheet 4Nov. 7,v 1933. J. w. JENKINS RAILROAD CROSSING GATE APPARATUS 6Sheets-Sheet 5 1 I I I I l I I l I I I l l g I l l l I l I l I l I I IIIIIIIII IIIIIIIII Y my W km. W NMJ .mz m NH4 hm, w n N. m @www @if sww, www@ wwwm. m w I :P l V if @INN m NNN m HTNN: m HWNNNI HHHINNNI E Iim u s m Im -L ,L NOI @NNI QQ. J z NNN] .Wmv .OUQ WQWKOQ NIR@ QN W NEINQ Nov. 7, 1933. .1 w. JENKINS A RAILROAD CROSSING GATE APPARATUS FiledApril` 14, 19430 s sheets-sneet 6 ANN. lll HtllLHl. @KJ l wim? REWE J.

Patented Nov. 7, 1933 UNiTED STATES RAILROAD CROSSING GATE APPARATUSJames W. Jenkins, Chicago, Ill., assignor to The Buda Company, Harvey,Ill., a corporation of Illinois Application .April 14, 1930. Serial No.444,104

v 1 3 Claims.

This invention relates to automatic crossing gates and means foroperating the same and comprises features which render it adaptable toVarious track, tramo, and track signall conditions which may alreadyexist at a crossing to be guarded by gates.

It is preferred that each gate arm be operated by an individualreversible motor carried in the standard which supports the gates, andthat the operation of each motor be governed' by a gate control relaywhich for safetys sake should be held in operated condition normally andreleased upon the approach of .a train, thus setting in operation themotor which will then bring the gate arm down into barrier position.Should the circuit which holds this gate Vcontrol relay normallyoperated become opened or fail through any cause whatsoever, the gatearm will lbe brought down to barrier position. Various circuits aredisclosed herein forcausing the release of the gate control relayatproper times for closing the gates and also for opening them.

One of the objects of this invention is to provide crossing gates andoperating circuits therefor having a number of safety features in thecircuits which will protect the crossing even shouldl remains on thecrossing.

Another object of this invention is to provide a gate control systemwhich can be installed on a railway already equipped with a block signalsystem Without-interference with the 'existing-sig nal system and soadaptable that no matterv Another object of this invention is toprovidea crossing gate arm and operating means therefor which willpermit manual raising ofthe gates from barrier position to permit thedisengagement of the gate arms from between thel stakes` of for usewhere there is no signal system already in `native train controlledcircuits.

trucks, should the gate 'arms such a position.

Other equally important objects and advantages of this invention, toonumerous to list here as such, should become apparent upon a perusal ofthe specification anddrawings.

In the drawings,

Fig. 1 shows a vertical central section of a gate standard,

Fig. 2 is a plan view o1' the gate standard partly 65 in section showingparticularly the sidewalk arm drop down into mechanism,

Fig. 3 is a side elevation of part of the sidewalk arm mechanism, ,A

Fig. 4 is a plan view ofl a detail walk arm construction,

Fig. 5 is a side elevation with portions in section with the same gate'standard showing the roadway and sidewalk arms in raised position,v

Fig. Gais a sectional view on line 6-6 of Fig. 7 75 showinga yieldswitch,

Fig. '7 is a side elevation of the same switch,

Fig. 8 is a plan view of portions of the roadway arm,

Fig. 9 is a schematic representation of a train 80 speed controlledcircuit connectable to the gate control circuits for operating the same,

Fig. 10 is a schematic representation of the gate controlled circuit,

Fig. 11 is a schematic representation ofV another 85 embodiment of atrain controlled circuit,

Fig. 12 is a schematic representation of a further embodiment of a traincontrolled circuit of the sidev existence,

Fig. 13 is a' diagrammatic disclosure of one form of a time elementrelay which is used in the train controlled circuits,

Fig. 14 is an enlarged vertical sectional view showing the details ofconstructionof the dash pot mechanism, Fig. 15 is a horizontal sectionon the line 15--15 of Fig. 5 showing the position' of the dash potrelative to the center of the housing, and Y Fig. 16:is a diagrammaticdisclosure of one form 100 of a time element relay to be used with the'circuit of Fig. 9.

The same gate control circuit may be used without change with either ofthe three alter Y 105 Each crossing will be provided with one or morebut preferably four gate standards each bearing a roadway arm, and ifthere are sidewalks at the crossing the gate standards will also supportvsidewalk arms. Eachstandard-will 11o have a base plate 1 fixed on aconcrete base and supporting an immovable or stationary housing 2.Mounted above the housing for rotation relative thereto is a housinghead 3 at one side of which is a suitable bearing 4 for rotatably supporting the gate arm channel member generally indicated as 46. A packingring 5 carried by the housing head contacts with the uppermost edge ofthe housing to prevent the entry of dust but permits free movement ofthe housing head with relation to the housing.` One or more rollerscarried by frame 8 bear against a track 7 on housing 2 and aid incentering and guiding the rotation of the housing head. llltigidlyconnected to the housing head is frame. 8 provided with a mechanismplate 9 for supporting the reversible motor 11. The weight of the frame,motor, and gear assembly, head arms, etc. is supported through the cams104 and 164 of the mechanism plate on springs 99 and 99 and held to ahorizontal plane by means of thrust bearings 13 and 13', the lattersurrounding the depending post l2 which is .threaded into the mechanismplatee. The two thrust bearings engage the uppery and lower margins ofthe flanged opening on the top ofV the hollow post 1'4, while anysuitable thrust retainer such as the retainer 91 may-be employed to holdthe assemblyin operative position.

Operation of roadway arms Thelmotor 111drives'a1train of gears generallyindicated 'as 15, one of which, 16, is keyed Vtothe shaft 17 which shaftis also equipped with a worm gear 18. The Worm gear 18 drives thesegmental worm wheel 19and'causes the reciprocation of the connectingrod 21, the'latter 'being pivotallyA connected to the gear-19 and thecrank arm' 22. This crank arm is keyed to the middle portion of theshaft 23, which upon rotation causes the roadway'arm and sidewalk arm tobe raised or lowered in a manner described below.

Rotatably mounted on the Vshaft 23 `bearing on a brass bushing 23 isa-*sleeve 24 having an annular ilange 24. A sector gear 25 is mounted onthe .exteriorsurface of thesleeve 24 and meshes with anothersector gear25' for raising and lowering the sidewalk arm. A pin extends through thesector gear` 25,.the flange 24' and the channel member 45, causing thesethree members" ailhe shaft 23! also has keyed thereto a crank arm26which, :as is bestshown in Fig. 5, ex-

Y tends rearwardly away from the roadway within thef channel vofthefroadway arm and normally iscentered betweentwo opposed compression lsprings 27 and 28 which aresufliciently strongV tocause4 the roadway'armnormally to be raised and lowered 'as the crank arm V26 isoscillated;` substantial disalignment of the` center. lines of theroadwayv arm` and the crank An opening in .the arm 26 surroundswithout:any

armx26 the middle xed enlargement on the spring guide pin-26' which isrigidlymounted in the channel 45.. The 'spring retaining cups Z'Vand28', in which the ends of their respectively asso'- ciatedsprings rest,normall'yabut against this enlargement and are slidably disposed on thepin, hence should the channel beheld against rotation by an obstructionwhile the motor is rotating the .arm.26, that arm will not"remaincentered but will move against the cup 2 or the cup 28', as the case maybe, and compress the respectively associated spring. For example, shouldthe roadway arm strike an yobstruction such as the top of an automobile,and its further downward movement be prevented, the crank arm 26, stillbeing driven by the motor, may still continue to move a little furtherin a counterclockwise direction, as viewed in Fig. 5, and compress'thespring 28. The other spring 27 will not expand due to the abutment ofits cup'27 against theenlargement on the pin. It is obvious that when`this obstruction is removed the'spring 28 will quickly restore thecrank arm 26 and roadway arm to their usual parallel alignment.

Yield switches kShould this obstruction, such as an automobile top,oppose the downward movement of the roadway arm before it has reachedbarrier position, the vcontinued counter-clockwise movement of the crankarm 26 Will not only compress the spring 28 but the head 29 of the crankarm will kick open the upper toggle switch 31 and open the down drivecircuit which passes through the contacts of that switch. Should a childhang onto the gate when the updrive circuit is in operation the lowertoggle switch 37 will be kicked open toy open the updrive circuit andstop the motor until the child lets go of the gate. A description'of theoperation of .the updrive toggle switch will suflice for anunderstanding of the operation of both the updrive and downdrive toggleswitches. One side only ofthe updrive circuit passes through the switch37, en.- tering atv the binding post 32, continuing through the springcontact 33, across the conductor contact block 34, and out again throughthe spring contact 35, binding post 36, and through the remainder oftheupdrive circuit. holds the trip ngers `39 and 39 of the two toggleswitches tightly against the head 29 or the crank arm. The spring 38thus restores either toggle switch to normal when the centering springs27` and 28 have realigned the crank arm and roadway arm. The trip finger39 and bifurcated arms 41 constitute a rigid bell crank, and.. whenthisY crank is rotated about pin 37 counter-clockwise from its normalposition, as shown 1in Fig.A 7, the associated toggle springs 42 will,after dead center has been passed, snap the Contact bell crank 43 out ofcontact position, that is, clockwise as viewed in Fig. 7, removing thecontact block 34 from contact with the spring contacts?, and thusopening the associated lil updrive circuit. An insulating block 44provides a suitable means Afor attaching the contact block 34 to thebell crank 43. The provision of the togle switches 31 and 37'preventsinjury of the motor'or Vblowing of fuses in the emergencies i' abovedescribed.

Theroadway arm consists of parallel channel frame members 45 and 46mounted on opposite sides ofthe gatestandards, the channel 45 being Aspring 38 supported on the sleeve 24, while channel 46 issupportedrotatablyy on the bearing 4. (See Fig. 2). On the rear end ofthe channel members 45 and 46 are carried counterweights 47 and 48.Connected to ythe roadway side of the frame members 45 and V46 areboards-45' and 46', prei- 52 which furnish supports for exible cables 53and 54 which extend backto the frame members 45 and Lie'and are anchoredthereto, as shown in Figs. 2 and 3. The combination f the cables and theboards forms a light-weight, but rigid, gate arm and there is the addedadvantage that the ilexible cables 53` and 54 will absorb some of theforce of collisions and protect the boards from fracture.` It ispreferred that the block e9 carry a light-weight tubular member 55, madepreferably of aluminum, which will extend out to the center of theroadway, there to meet another gate arm of similar constructionextending from the standard on the opposite side of the roadway. Thegate arm may extend completely across the roadway.

rhe channels 45 and 46 are rigidly connected together by a front angleiron 56 and at the rear by the bumper shaft 57. As shown in Fig. theshaft 57 may bump against the base of the pedestal to limit upwardswinging movement of the gate arm. The gate channel member is preferablya channel iron which is deep enough to provide a suitable housing forthe crank armV 25 and the toggle switches 31 and 37. The space thusprovided in the channel arm may be inclosed by a cover 59, thusprotecting the switch mechanism from the elements.

Lima swr-:ches

gate standard is provided with updrive downdrive limit switches forstopping `the reversible motor when the gate arin has reached eithe thebarrier or the clear position. l shows a switch operating ringer 6ladapted to strike the trip lever 62 of the toggle switch generallyindicated at 62', tov open and hold open the saine to stop the updriveofthe roadway arin as it reaches maximum raised position, the operatingnger being mounted to rotate with the shaft 23, while the toggle switch52 is mounted in stationary position in the housing head .3j in anysuitable' manner. The construction of this toggle switch is prefer-a lythe vsaine as that ot the toggle switch shown in Figso and 7, exceptgthat it is normally urged toward closed position by a 63 connected toaspring anchor support Se mounted in any` su ble manner in the housinghead. The spring will close this switch as soon the finger 6l moves awaytroni it during the down drive or" the roadway rhe actuation or thistoggle switch will be understood hy reference to the foregoingdescription ci the toggle switch shown in Figs. 6 and 7.

Another switch operating ringer 65, shown in l, rotates with shaft 23and trips a toggle switch generally indicated as 66 to open and hold`open the same when the roadway arm has reached its lowermost on, thusopening the downm drive circi lne construction oi this switch iidentical i of the toggle switch 62 and needs no L irther description.

M anual lifting which will be depressed providedsorneone manuallyliitsandthus rotates the gate arin upwardly while the crank arrn 2dremains stationary. When the roadway arm has 1eeen manuallyv rotatedclockwise, as viewed in 5, suiicicntly to cause Vthe button or" neswitch 67. to strike and be ressed by the crank arm 2G, a circuit,

as shown inFig. l0, will be closed, regardless ci the status ci thetrain controlledeircuits, to operate the gate .control relay and thusclose an updrive circuit to motor of the particular gate arm which. isbeing lifted, whereupon the motor willraise this gate arm until themanual pressure thereon hasbeen released. With the u movement i the gatearm the `down dive lirnit switch will close. With the release oi thismanual 3 assure the equaliaing spring 2S will realign the crank arm 25and the gate arm, thus opening the switch 67 and causing the release ofthe gate .control relay should therebe at time no other circui such atrain controlied circuit, closed othe ay' operated. It the circuits areat this moment so set that gate arrn should come down, the rele 1e or"the gate control relay, wililater scher-ter underfJ stood, will againclose the downdrive circuit to the as ciated'rnotor ane Y 'ng the gatedown to barrier position whereuponthe:l associated downdrive limitswitch will. ce opened, thus stopping the motor. The position ol' thepush buttonv switch 6'7- in the circuit indicated in Fig. l0 on theschematic.

Sidewalk The sidewalk arm is constructed and operated as follows: IAhorizontal shaft 'Il is supported for rotation .in brackets "d andl 73,which are supported rigidly on the housin head, and keyed to it thesector gear25 and the yoke Carried at the outer end ci the yoke is asocket 'dhaving liiurcated portions 5'6 and 77. Pivoted on the i in 73and carie-d between the bifurcations is a head '.79 at the outer end ciwhich is carried `the ain portion Sl of the sidewalkfarrn, preierahly inthe forno of a light-weight hollow metallic tube. inner end or". head i9is r seed to form. a nf-zgativeV cani suriace having the shape shown inTr e 2. I'he socket 75 also carries an e fti'cal member 83,' the planview of which is shown in dient and onthe outer surface or" which bear apa and 85, the opposite endso` anchored at 86 to thcalv 8B and sprprovided forthe purpose or" arm to reina-in nornrialiyv este ded'transversely across the sidewalk but te permit this arni, against thepressure oi. sp- .ig-s to swing horizontally about the pivot 73. Thisteature 'is provided' so that, the arin an.. housing head are rotated pyniet striking the roadway arm, although also will naturally be swungaround, t esidewgalk arni 8l may fold back its pivot "i8 in oase ithappens to strike a i when rotating. Thus the pedestrianwould'be savedfrom any injury. f

In order to hold the side-w lk arni positively extended in normalposition w 'ithe gate is up there is provided a locking pi .nger 8'?which will extend into the negative cani 82 when the side walk arm israised and only when raised. Referring to 2, 3 l5A it will be noted thatthis locking plunger is connected hy the link 88 to a pivot 89 which issupported on Ythe housing head somewhat above the shaft 71. Thus as thesidewalk arm is being raised the locking pin 87 will be moved upwardlyand outwardly in an obvious manner until it engages in the negativeoamand finally seats itself therein as shown'in Fig. 5, thus preventingthe wind or anything else from moving the sidewalk arm out of its properextended position. However, as soon as the sidewalk arm is lowered againthe locking pin will be withdrawn from the cam and leave the sidewalkarm free to be moved out of its normal position if that be necessary.The cam 83 and the springs 84 and 85 will cooperate always to return thesidewalk arm to normal position as soon as the obstruction has beenremoved.

Should a child hang on to the lowered sidewalk arms before the updrivecircuit becomes closed, his weight imposed on the arm will urge the yoke74 to push the bumper bar 57 downwardly. However, this force will notcause the roadway arm to be lifted in view ofthe fact that any furtherdownward movement of the yoke 74 will rotate the sector gear in aclockwise direction, (Fig. 3)v and cause the sector gear 25 to rotatecounterclockwise, whereupon the connecting pin which causes the sectorgear 25 and the channel member to move as a unit, will, in such a case,urge the roadway arm to move counter-clockwise also, thus pushing thebumper shaft 57 upwardly against the under side of the yoke. Thus acounter balance of forces would be established, with perhaps a littleaid contributed by the compression springs 27 and 28 carried in thechannel member.

However, should the child be hanging onto the lowered sidewalk arm atthe time the updrive circuit becomes closed, the weight of the childwill tend to rotate the roadway arms counter-clockwise through theaction of the sector gears 25' and 25 and the pin 30. In the meantimethe motor will be rotating the crank arm 26 clockwise, and if the childsweight is suiiicient to prevent the roadway arm from rotating' Y centerline of the crank arm 26 whereupon the spring 38 will close the toggleswitch 37, closing the updrive circuit to the motor and enabling theering of the gate. Acareful examination of they circuit disclosedherewith will reveal that the aocidental or malicious obstructing ofdownward or upward movement of the roadway and sidewalk arms will neverthrow the circuit controlling the gate into sucha position that thecrossing would be left unguarded during the approach of a train.

Deflection of gates In order to restore the roadway barrier to itstransverse position across the roadway after it has been deflectedtherefrom by a vehicle, and to hold it normally in that position againstthe force of the wind there are provided two springs 99 and 99 Vmountedon plunger guides 97 and 98 which in turn are mounted onthe baseplate 1. Mounted within the plunger guides 97 and 98 and upon thesprings 99'and 99 are plungers 92 and 93 whose upper ends carry ballbearing cam follower rollers 101 and 102 `pinned .to the plungers bypins 94v and 95. Passing through the plunger guides97 and 98 and slots96 and 96' in the plungers 92 and 93 arepins 96a and 96a which align theplungers during their vertical motion which will Vbe described below.The rollers 101 and 102 normally are Aheld against the low points ofcams 104 and 104 by initial pressure in springs 99 and 99'. Mounted inthe vertical post 14 are thrust bearings 13 and 13 through which passthe retainer 91 which threads into extension 12 of mechanism plate 9 andshoulders against thrust bearing 13. Spacer 103 separates extension 12,mechanism plate 9 and thrust bearing 13. Since vertical post 14 isbolted to base plate 1, obviouslywhen the roadway arm is in the barrierpositiony and is deflected horizontally, causing therotation of thehousing head and the gate driving assembly, the Vmechanism plate 9 willnecessarily rotate relatively to the cam follower rollers v102 and 103and the curved surface of the cam actingagainst the rollers will causethem to move downwardly thus causing plungers 92 and 93 to movedownwardand compress springs 99 and 99'. As soon as the pressure is relievedfrom the roadway arm which had caused it to be deflected from its normaltransverse position across the roadway the action of springs 99 and 99against the plungers 92 and 93 will urge the cam follower rollers 101and y102 upwardly against the cam surfaces 104 and 104 and obviouslythis upward force acting against curved cam surfaces will cause themot-or base 9, driving assembly, head, etc., to rotate back tonormalposition thus compelling the gate arm to return tonormal'transverse position. The low points of cams 104 and 104 intersectin a wide V which acts as a notch for the rollers to settle into andthus when the roadway arm is in the normal transverse position it isheld against wind pressure requiring an impact to start the horizontalmovement.

For delaying the return of the gate arms from deflected position, thuseliminating dangerous whipping, there is provided a hall 106 which isheld against the cam 104. The ball 106 is carried in the socket at theupper end of a plunger rod 107. v The lower `end of the plunger rodabuts the top of the center post 108 which is formed integrally with thepiston 109. The outer part'of the piston comprises an annular shell 111formed integrallytherewith and bearing on the interior of the dashpot`112. Between the core and the outer shell of thn piston is disposedvan annularcompression spring 113 whichurges the iston upwardly.

` When the roadway arm isi'n barrier position and is deflectedhorizontally, causing the rotation of the housing head and the gatedriving assembly, the in otor base 9 will necessarily rotate relativelyto the cam follower 106 while the spring 113 will urge the piston 109upwardly with the follower 106 riding uinvardlyy along the curvedsurface of the cam 104. During this upward movement of the piston andcam follower the valve 114 which is normally held closed by the weakspring 115 will be opened by the difference of pressure on its upper andlower faces permitting the air at atmospheric pressure, oil or otherliquid filler to enter through the port 116 in the piston head, thencepast the valve 114 which is now raised from its seat 117, thence througha plurality of ports 118 into the bottom of the dash pot. This `inowwill be rapid and will enable the plunger rod 107 and follower 106 tofollow quickly the rotating cam 104. As soon as the pressure whichdeflected the roadway arm is re.- lieved the action of the spring 99 and99V in the base of the standard will cause the gate arm to swingbackwardly toward normal position with considerable force. However, thedash pot mechanism at this time operates to prevent a sudden whippingbackward of the gate such as might endanger other vehicles toward whichthe returning gate arm is swinging. The return of the gate arm willforce the follower 106 and plunger rod 107 downwardly, immediatelyclosing the air valve 114 by a reversal of the pressure differential onits opposite faces and causing compressiony of the air or liquid whichis below this valve. The

pressure thus built up will retard the rotation ofl cam 104 and the gatearm but will be slowly relieved at a speed determined by the size of thevent 119 which extends through the valve 114, thus compelling the gate.arm to return to normal transverse position at a pre-determined'safespeed.

Gate control circuit The relay contacts inthe circuits to be describedwill be referred to as make contacts meaning contacts which are madeupon the energizinfT of the relay, and break contacts, the lattermeaning contacts whichA are broken when the relay is energized.

The gate control circuits shown in Fig. 10,:the operation of which willnow be described withk reference to the schematic, has been in a largemeasure described above along with the explanation of t operation of thegate arms. The circuit here shown' controls the operation of four gatessuch i as will usually be installed at each railroad crossng. That is,four gate standards each containing a reversible motor and each equippedwith a roadway arm and in some cases also a sidewalk arm will be theusual equipment." The circuits which control the four motors arevexactlyalike,- hence the description of one will suffice for all,

as is indicated in the schematic of Fig. 10 the motor control relay isenergized by the signal current which may be and is preferably the sameksignal current which is used in the train controlled circuits. Thecurrent for operating'the motors, however, is preferably supplied from apower supply source at each crossing.

10 shows the gate control circuits for the four motors with the switchesand relays inthe positions which they will have when the gates are fullyraised and no train is approaching the crossing. Y *A Each motor isprovided with a motor control relay 121 which may be mounted preferablyinside of the gate standard. It is preferred that, normally when thegates are raised, or in the clear position, this motor control relay beheldv energized, and that its release cause the associated motor todrive the gate downwardly. This arrangement is preferred to a systemwhich would require a relay to be energized to drive the gate down inorder'to guard the crossing. Conseduently, when using the circuitprovided in this invention should the signal current which holds relayoperated fail through any cause whatsoever, the gate arm will come downand guard the crossing. One terminal of the motor control relayconnected to the ground side of the signal supply system, or asillustrated in the schematic and using the terminology of this art, thisterminal is connected to'CX through the line 122. Battery, or BX, forholding this relay 0perative when no train is approaching Vthe crossingvwill lie-supplied Vthrough line 123, battery bev ing held on this Vlinethrough any one of the several train controlled circuits which aredescribed hereinafter. l

When "the motor control relay 121 is held energized .the downdrivecircuit through the break 8,5 contact on this relay will be open and theupdrive circuit willbe closed from battery from ,the power supplythrough YswitchlZe through the make contact ol' relay 121 asfar as theupdrive limit switch 62 which is shown in the schematic 9 0 inopenposition, as would be the case whenrthe gate is in fully raisedposition. ,It will be vob served thatprior` tothe opening of the updrivelimit switch the updrive circuit would previously have been closedthrough, 62 and through the 95 yield switch 37 to the up winding ofy thereversible motor and thence to.4 ground in the power supply. Should atrain approach the crossing and cause ther opening of the BX lead to themotor control relay, that relay will then release and` itsrbreak contactwill close the downdrive circuit frompower through the downdrive limitswitch whichis at this time closed, through the yield switch 31, throughthe down winding of the motor and back to power. Since all four motorcontrol relays 121 were previously held energized by the, same `BX lead,they simultaneously release` and all "four motors will bring theirassociated gate arms down through a mechanical operation that has `beeneX- plained above. lWhen thegate armsy reach full lowered position eachdowndrive limit switch 66 will f be kicked open thus opening thedowndrive circuit and stopping each motor. lt will be remembered that assoon as the gate arm starts to come down the updrive limit switch willbe restored to closed position through the vaction ,of its restoringspring 63. Ordinarily the train controlled Vcircuit will hold the BXsupply tothe gatecontrol relay open for sometime, that is, un- 120 tilthe train-has passed the crossing.

While the gateis down the roadway arm may be lifted manually andthereby, as vdescribed above, close the push button switch 67 on theassociated gate arm kand supplyy BX through lead 125 125, as theschematic indicates, to the motor control relay which is associated withthe arm thus lifted. At thistime the closing of the push `button switch67 will energize the relay 121 and close the. updrive circuit liftingthe gate arm until pressure on the push button switch has been released.In the meantime the downdriveilimit-switch, hay ing been restored toclosed position, will be ready to re-establish the downdrive circuit assoonas theropening of the switch 67. causes the release of the relay121.`

Whenthe train controlled circuit again supplies BX to all four relays121, as would occur after the train passes, each of these relays Ywilllbecome energized again, close the updrive cir.- le@ cuits and their-motors will then raise the gate arms until the updrive limit switchesare kicked open mechanically. f

Reference to the foregoing description ofthe toggle yield switches 3land 37 will serve for a complete understanding of theirfunctioning inthe schematic of Fig. 10. It may be stated khere thatthe updrive yieldswitch, or toggle switch 37,` is placed the updrive circuitv and willalways N be closed except Whensome force opposes the Tlf/ lifting of thegates and opens this switch. The downdrive yield switch, or toggleswitch 31, is placed in the downdrive` circuit and will always pass thecurrent except when some obstruction opposes the -downward movement ofkthe gate arms and enables the crank arm 26 to kick open this toggleswitch. l

Train controlled circuit (Fig.l11)

The circuit shown schematically in Fig. 11 is one that will control thecrossing gateY control circuit of Fig. 10 and is intended for use withrailroads having one or more tracks and a block signal systemalreadyinstalled. The relays of the circuit are shown in the positionsthey will normally havewhen no Vtrains are within the blocks indicatedin the schematic. In order to bring the gates down to barrier positionbefore an approaching train reaches thecrossing the train at a positionremote from the crossing sets into operation the equipment necessary forlowering the gates. Certain features of this train controlled circuitmake it unnecessary to disturb the existing block signal system, if thesignal system is provided with theusual track relay at the entrance ofeach block such for example 'as the track relays' 131, 132, 134 and 135.Each track relay will always be .held energized bya circuit through therails until the trucks of a train enter the block and shunt out thetrack relay' at the entrance of the block. The beginning and ends of theblocks are indicated in Fig. 11 by the lines intersecting the rails atthe positions A, B and C. I When the track relay 132 is shunted by thetrucks of an aproaching train moving in the direction of the arrow ontheeastbound track No. 1, the makeA contact connected to the line wire136 Vwill be opened thus removing BX, or battery, from the repeat relay137 andA causing that relay to release. It is evident that the trackrelay 132 will remain cle-energized so long as any truck of the trainremains within the block AB. The line wire l36'is the only wirenecessary to be carried from this track relay to the crossing where therest of the control equipment is located. In cases where the track relayis a mile or more from the crossingV the u'se of only one line wire pertrack is an important consideration.

Therelease of the repeat relay 137 establishes a. circuit from BXthrough the break contact lof this relay and the wire138 through thecoil of the time element relay 139 and thence to CX, thus energizing thetime element relay. The construction and operation of the time elementrelay may be better understood by reference to Fig.`13, wherein theparts are represented `somewhat Ydiagrammatically.

The time element relay is shown in Fig. 13 with the slot coil energized,and the slot arm threadedly engaged with the worm and lifted about halfof its distance of travel toward the lifter finger. At this time all ofthe contactsare in the normal position they would have prior to theenergizing of the slot coil relay.

When the lead 138 through the break contact ofthe repeat relay 137supplies battery to the slot coil 141 a circuit is thereupon establishedto CX through the lead 142 energizing the slot coil, rotating thepivoted lever 143 to the left and pulling the arm 144 likewise to theleft causing the right margin of the elongated slot 145 which looselysurrounds the time Screw 146 into contact with the threads on the timescrew. A few threads areprovided on the inner surfaceofthe right .marginof the slot `to engage the threads of thetime screw so that rotation ofthe ltime screw will swing the arm l44upwardly as viewed in Fig. 13,rotating about its pivot 147. The time screw is rotated by the motor 148the circuit for which is closed from BX through the lead 138, the breakcontact 149, binding post 150 through the winding of the motor CX. Anysuitable train of gears such as those shown will thereupon cause thetime-screw to rotate at a predeter- Vmined speed governed by the gearratio to cause the lifter pin 151 in a desired number of seconds afterthe start of the motor to raise the lifter nger 152 and break thespringcontacts 149 and 153. .When 'the contact 149 is opened the BX supplywill be cut oT from the motor causing the latter to stop, but the slotcoil will still remain energized. At the same time the contact 153 willbe opened-cutting off the BX supply from the gate control relay 154, therelease of which will thereupon cut off .BX from the motor controlrelays 121', causing the gates to lower. The purpose ofthe time elementrelay is to cause the gates to start lowering a predetermined number ofseconds after-a train shunts out the track relay so that the gates willbe in barrier position in ample time before the train reaches thecrossing. It Vis evident that by Varying the gear ratio the gate closingtime interval may be varied to comply with dierent conditions that maybeencountered, such as different lengths of signal system blocks,diilerent requirements of the laws relating to'gate closing, and inaccordance with differently calculated maximum train speeds. When Vtheslot coil subsequently becomes deenergized,y as will later be explained,the spring 155 will pull the'pivoted lever 143 and the slot arm 144 tothe right disengaging the threaded slot 145 'from the time screw andpermitting the slot arm 144 to drop by gravity back to its normalreleased position where the arm 144 may bump against the adjustable stopscrew 156.

In the schematic the time element relay 139 is indicated as is customaryin this art showing a pointer 157 as though the pointer rotatedmaintaining the BX circuitfor the relay 154 so long as the arrow of thepointer remains in contact with the ksolid line and breaking thatContact thereafter. 'Howeven what actually occurs has been describedabove in connection with Fig. 13.

. The train oncehaving entered the block AB and released the tracksignal relay 132 and the repeat relay 137, even though the track relaywill again operate as ,soon as the last truck of the train leaves theblock AB the repeat relay cannot again operate until with the trackrelay energized a truck of the train rolls onto the short one-railcircuit 158 and shunts out the hold relay 159. The short rail 158 may beinsulated as is schematically indicated from the remainder of the track.A bond 161'may be extended around this short insulated rail'to avoidinterfering with the existing block signal system. In place of the shortrail circuit, one may use, if desired, a track instrument, schematicallyindicated, such as 163 and 164 placed under the rail and depressed bythe weight of a train passing thereover to open its contacts. Any one ofseveral well known track instruments may be employed for this purposeand their construction is so well known in the art as to require noexplanation here. As' soon as the last truck of the train has clearedthe blockAB and while a truck of the train still has the hold relayshunted out a circuit is closed from BX supply through themake contactof the track relay 132,

Cil

through the coil of the repeat relay 137, through the break contact ofthe hold relay 159 to CX. As soon as the repeat relay becomes energizedit will then stick in that condition by completing its control circuitto CX through its own make contact, it thereafter remaining energizedindependent of the hold relay. When the repeat relay becomes operatedthe time element relay 139 will release and all of its parts will berestored to normal position. However, even though the release ofthe'time element relay will restore batteryto the gate control relay 154yet the latter cannot become operated because its circuit to CX is nowheld open through the make contact of the deenergized hold relay.However, as soon as the last truck of the train'passes beyond thecrossing and allows the hold relay to reoperate the circuit through thegate control relay will then be .cornpleted and the BX supply to thegate control circuits will be restored, raising the gates.

A train approaching a crossing on the eastbound track number 2 willutilize the track signal relay 131, the repeat relay 165, the timeelement relay 139, the gate control relay 154 and the hold relay 166 tocontrol the operation or the crossing gates, these relays operating, asis obvious, inthe samemanneras do the relays associated with tracknumber 1. A train approaching on the westbound track number 3 willutilize the'track relay 134, the repeat relay 167, the time elementrelay 163, the gate control relay 169 and the hold relay 171 forcontrolling the crossing gates. A train on the westbound track number 4will'utilize the track relay 135, the repeat relay 172, the time elementrelay 169 and the hold relay 173 `for controlling the crossing gates.Even though one or more trains are approaching the crossing and one ormore may also be on or leaving the crossing the circuits for the fourtracks are so interconnected that in no instance will the gates remainup orV go up at a time when they shouldbe down and guarding thecrossing.

Train controlled circuit (Fig. 12)

This circuit shown in Fig. 12 with all relays in normal position isprovided. for use at a crossing on a railroad which is not alreadyequipped with a signal system employing track relays. Hence it isnecessary to provide each track either with a short insulated rail 174,and a bond wire 175, as shown in the eastbound track or with a trackinstrument switch 176, the latter being shown on the westbound track,each controlling a specially installed track relay 177 and 178,respectively. The short one rail circuit orthe track instrument switch,will in a simplified installation be set in the track a sufficientdistance from the crossing so that when a train at maximum speedreleases either of these track relays the associated mechanism may havesufficient time to bring the gates to lowered position well in advanceof the arrival of the train at the crossing. The line wires 179 and 181will therefore be provided paralleling the tracks to the crossing. Theshunting out of the track relay 177 by the trucks of a train rollingonto the short insulated rail 174 will cut oi.F BX from the gate controlrelay 182 which then releases and cuts oir BX from the lead 123, whichlatter lead is to be connected to the BX lead 123 in the gate controlcircuit. The cutting or of BX from the gate control circuit willthereupon cause the gates to he lowered as has been explained above. Assoon as the last truck of a train rolls off the short rail 174 the trackrelay 177 will re-operate but the control relay 182 cannot re-operate atthis time unless and until the iront end of the train reaches the shortinsulated rail 183 at the crossing and shunts out the hold relay 184.When the hold relay is thus released a circuit to operate the controlrelay 182 vwill be closed from BX through the make contact of the trackrelay 177 through the coils of relay 182 through the break contact ofthe released hold relay, thence to CX. As soon as thisrelay operates itwill then stick itself through its make contact, being thereafterindependent or relay 134. The energizing of the relay 182 while a trainis still on the crossingwill restore BX to the gate control circuit, butwill not cause the gates to rise because at this time the de-energizedhold relay 184 will havexopened the circuit to CX from the lead 122".When the circuit oi' Fig. 12 is used with the gate control circuit ofFig. 10 the CX lead 122 will be connected to the CX lead 122, the latterbeing in the gate control circuit. The gate control circuit will not beoperated to raise the gates until the last truck of thev train has leftthe short rail 183 whereupon the hold relay at the. crossing willre-operate and restore the circuit CX from the gate control circuit.Power at this time then being supplied to the gate control circuit,lthatcircuit will cause the gates to rise.

The westbound track lis shown equipped with track instrument switches176 v and 185 which operate by the pressure of a car upon the railunderneath which these switches are placed. The Westbound track is'provided with the hold relay 186 and the control relay 187 whoseoperation will be understood by reference to the previous description ofoperation of relays for the eastbound track. In order that BX may besupplied to the push button switches 67 in the gate control circuit ofFig. 10 there is provided a BX lead .125" for connection to the BXlead125 in the gate control circuit.

Speed controlled circuit (Fig. 9)

The speed controlled circuit shown in Fig. 9 is illustrated with all ofits relays in the normal position which they would have when no trainsare within the track areas shown in the drawings.

The circuit, which may be used with the gate control circuit of Fig. 10,is designed especially yfor operating the crossing gatesv under the con-Such directionv of travel of trains which may enter the control area,stop and back out again.

. The track area M is such that a train traveling at sc miles per hourwill just travel the distance M in 'y seconds.` The length N plus O lissuch a distance that a train traveling therethrough at maximum speed,faster than x miles per hour, will reach the crossing e seconds afterthe gates are down. e seconds will be the length of time that the gatesmust be down before the train reaches the crossing to satisfy theregulations of the railroad. The space O issuch that a train travelingat :c miles per hour therethrough may. initiate the lowering of thegates upon entering space O and reach the crossing c seconds afterthegates are down. 1

A track relayv TRl is provided in the southbound track, being providedwith a' shortenerail circuit. for holding it normally operated, as isindicated. At a distance L further north on track, a greater than theestimated length oi the longest train which may use this track, anothershort one-rail circuit is provided and equipped with Aa track relay K1.

The gates are normally, held in raised position by maintaining BX on thelead 123'", which is connected to the BX lead 123 in the gate controlcircuit o lo; BX is normally supplied on this BXlead through the makecontacts of the CX is maind 122'" to the gate through the make nergizedhold relays tained normali control circuit contacts oi the normally TRfiand TR-.

Assuming that a train traveling at .t inilesper hour, or slowerapproaches on the southbound track, as soon it rolls onto the insulatedshort Y rail it shunts out the relay X1 which is connected thereto. Therelease of this relay will `cut off CX from the time element relay TELto release the latter if it should happen to be energized at the time.VAs the train proceeds further it rolls on" the short rail to which relayXl is connected permitting that relay to become energized again.Subsequently the train rolls onto the short insulated rail connected tothe relay TR1 whereupon that relay is shunted out and removes RX fromthe relay SR1 causing the latter relay in turn to release. The releaseof the relay SR1 will start the operation of the time element relay TElby supplying BX from the lead BX2 through a break contact of SR1 throughthe coil of line FCPl, make contact of lil, line FCP2, malte contact ofTRS and thence to 0X4. The train oi' gears in the time element relaywill 'ce arranged to cause that relay in y seconds after its slot coilhas been energized and its motor started to raise the lifter iinger tobreak the normally closed contacts and to close certain open contacts.

When the release oi the SR1 relay connects "5X2 to the slot coil 191 oithe time element relay TEl, BX is simultaneously supplied `g. 16)through the binding post P2 anda ilezii nector to the spring contacter192, the latter being mounted in the end oi an insulating block 193which is mounted on a spring contact lever 194. The circuit is completedthrough binding post P7 through the motor, through the winding of motorto FCPl, the slot coil and the motor bec ing operated simultaneously.The time screw then begins to rotate and the slot arm 1:25 travelsupwardly and y seconds after the motor is energized the lifter 196 willstrike the lifter finger 197 and break the contact 192, thus cutting onqBX from the motor and stopping the saine. As soon as the time elementrelay tripped its slot coil will stick in operated position by a circuitmaintained from the make contact of relay TCR3, CPB, binding post P1 andP2 of the time element relay, through the slot coil oi Athat relay, lineFCPl, make Contact of Xl, line lil-CP2, make con# tact of TRE to CXLl.`the green sig- At this t nal light G which was burning after'the trainhad left the Contact rail associated with relay K1 and before it hadcaused the time element relay to trip, will now be extinguished'upcn theopening of its circuit through Pn and P3. The yellow signal light Y, acautionary light, will remain lit through either of two circuits, onefrom BXS, make contact of TRB, line CPB, through binding posts P3 and P4of the time element relay, line YBX and through the yellow light to CX,the other circuit being traced from 3X2, make contact of TR2, bindingpost P4, to YBX, through the yellow light to CX.

At any time prior to the lapse of y seconds after energy has beenapplied to the time element relay TEL that is, before the relay trips,the time elementrelay is fully under the control ofy the releasedV SR1relay and if the latter relay again becomes energized during this periodoi y seconds the opening of its break contact will deenergize TEl, whichwill then immediatelyjdrop back to normal condition.V r

Assuming that the same train traveling at .r milesv per hour or` slowercontinues through the space M into the spaces N and O and passes thecrossing, at the time the. front trucks on the train reach the shortrail circuit to which TR2 relay is connected the time element relay willbe stuck through its own contacts in energized condition, as has beenexplained above, and the SR1 relay will still be released. The shuntingout of TR2 relay by the trucksof the train will, however, connect BX2through its upper break contact, through the winding of SR1 relay,thence through the lower break contact of TR2, thence to CXl, restoringSR1 to normal energized condition.

Thus far no circuit for lowering the gates will have been formed. Priorto the sticking of the time element relay and the shunting out of TR2,the SR2 relay obtained battery through the make contact of .TR2,-now itwill stillremain energized, preventing the gates from lowering as acircuit for holding relay SR2 energizedpreventing the gates fromlowering as a'circuit for holding relay SR2 energized will now beobtained from BXB through a make contact of TR3, line CPB, P3 and P4 ofthe time element relay, line CP2, another make contact of TRS,throughthe windingof SR2 and thence through theupper make contact of SR2to CX2. However, as the front trucks lof the train traveling at milesper hour reach the short insulated rail associated with TRS, thatrelaywill be shunted out and the battery circuit to SR2 supplied through thetwo make contacts of TR3 will be cut 'oir and' SR2 will release, cuttingoff BX from the gate control circuits of IFig. 10 and causing the gatesto lower. Thev shunting out of TRB also opens the stick circuit of TElrestoring the latter to normal deenergized condition. The distance O tothe crossing is of such alength that after the TRS relay has beenreleased by a train traveling at r miles per hour the gates will be infull lowered position e seconds before the train reaches the crossing.After the last ltrucks of the .train havecleared the short rail circuitof TRB that relay will again operate supplying BX tothe SR2 relay.Provided some part of the train is at this time at the crossing on theshort insulated rail to which relay TRA is connected, the shunting outof TPA will enable the SR2 relay to become energized by a circuit fromBX2 through the make contact of llO TR2, line CP2, a make contact ofTRB, winding t of SR2, break contact of TRl relay which is now released,thence to 0X2. Even though the SR2 relay now operates and places BX uponthe lead 123'", yet the shunting out of the crossing relay TR4 willwithhold CX from the CX lead'122" preventing the energizing of therelays 121'in the gate control circuits. Hence at this time the gatescannot rise. As soon as the SR2 relay operates it sticks itself throughits make contact getting CX through the lead CX2, and is no longerdependent for CX upon the break contact of TRA. As soon as the lasttruck of the train clears the crossing and TR4 once more becomesenergized the CX supply through the lead 122'" will be restored and thegates will rise.

Assuming that a train traveling at a speed greater 'than :r miles perhour enters the TR1 control area, the SR1 relay will be de-energized andthe time element relay set into operation in the manner described above.However, as it requires y seconds for the time element relay to trip andstick, the head of the train reaching the TR2 control area before theelapse of y seconds will shunt out the TR2 relay will immediately cutoir" the battery `from the SR2 relay, releasing the latter and causingthe gates to immediately start to lower, as may be necessary in orderthat the Uates may be lowered e' seconds before a train traveling,possibly at maximum speed, reaches the crossing. Simultaneously with theshunting out of TR2 and the release of SR2 the break contacts of TR2will close a circuit from BX2 through the winding of the SR1 relay toCXl, energize the SR1 relay and cut off battery from BXZ to the 'IElrelayA The release of the slot coil in the TEl relay will immediatelydisengage the threads of the slot arm 195 from the time screw 195 andthat relay will then drop back to normal de-energized condition. Thegates will remain down until after the last truck of the train passesbeyond the crossing whereupon the gates will rise due to a re-setting ofrelays which occurs in the same manner as was explained above inconnection with the movement of a train running at :c miles per hour.

Should a train run into the area M at less than :c miles per hour andinto the area N and stop within the area N the gates will not go downbecause of the functioning of the relays described above. However, thetrain after making a stop, as for example, at a local station, canproceed into the area O and beyond the crossing and the gates willoperate in time to protect the crossing. As soon as the train hasreached the track circuit of the TRB relay the shunting of that relaywill out oir the BX supply from the SR2 relay releasing that relay andlowering the gates. It

may be observed therefore that this circuit may be utilized where astation for local trains is positioned within the area N and thecrossing to be protected has a position relative to the station as shownin Fig. 9. The circuit will protect the crossing whether trains makingsuch a local stop approach it or whether through trains not making thislocal stop approach the crossing.v

Should a train run into the area O and stop and back out of O withoutcontinuing across the crossing, the gates of course will have beenlowered at least by that time but as the train backs across the shortrail circuit of the RESl relay and shunts out that relay, the CXS leadbecomes thereby connected to the SR2 relay which will be at this timereceiving battery through the make contact of the TRS relay, line CP2,make contact of the TR2 relay and BX2. The energizing of the SR2 relaywill thereupon raise the gates and clear the crossing. As the traincontinues to back through the area N it shunts out the TR2 relay cuttingoff BX from the SR2 relay, however, as soon as the train recedes beyondthe track circuit of TR2 and while cit is on the track circuit of relayRESZ both BX and CX will be connected to the SR2 relay to energize thesame and raise the gates promptly.

Circuits and relays for the north bound track correspond to those forthesouth bound track and are indicated by prime numbers and letters.Wherever short insulated rails are employed to establish short trackcircuits a track battery is shown connected thereto for energizing therelay associated with such circuit. Such a battery is indicated byreference character TB in Figs. 9, 11 and 12, and extensive duplicationof the reference is obviously unnecessary.

It should be understood that modifications of this invention differingin details of construction may be devised which will neverthelessernpioy the principles of this invention.

Having shown described my invention, I claim:

1. In combination, a railroad crossing horizontally pivoted signal arm,means for supporting the arm, operating means including motor, a trainof gears and a crank rotatable thereby for raising and lowering the rm,spring controlled means carried by said arm yieldably connecting saidcrank to said arm and means carried by said actuated by relativemovement of the arm and crank for stopping the action of the operatingmeans between the limits of its raising and lowering movements.

2. In combination, a railroad crossing horizontally pivoted signal arm,means for supporting the arm, operating means resiliently connected withsaid arm for raising and lowering the arm including a motor andelectrical circuits for controlling the operation or the same, andpressure actuated means including a switch to be tripped for opening themotor circuit to stop the action of the operating means between thelimit of its raising and lowering movements.

3. In combination, a railroad crossing honi- I zontally pivoted signalarm, means for supportingthe arm, operating means resiliently connected'with said arm for raising and lowering the arm including a motor andelectrical circuits for controlling the operation of the same, andpressure actuated means carried by said arm including a switch to betripped for opening the motor circuit to stop the action or" theoperating means between the limits of its raising and loweringmovements.

A4. In combination, a railroad crossing horizontally pivoted signal armand reversible means for operating the same including resilient drivingconnection thereto, means operable by a substantial yielding of saidconnection for stopping the operating means and means operable by afurther yielding in the same direction for starting the operating meansin a reverse direction.

5. In a crossing signal arm apparatus in combination, a horizontallypivoted signal arm, motor driven means including a rotatable crank foroperating said arm, said crank being connected to said arm throughspnings for yieldably driving the same, and means including a switchcontrolling the circuit to said motor actuated by movement of said crankrelative to said arm for opening the motor circuit to stop the operatingmeans.

6. In a crossing signal arm apparatus, in combination, a horizontallypivoted signal arm, motor driven means including a rotatable crank foroperating said arm, said being connected through springs to said arm foryieldably driving the same, the arm being held by said springs undernormal operating conditions in one position relative to said crank, andmeans including a switch controlling the circuit to said motor actuatedby relative movement of the crank and arm from said relative positionfor opening the motor circuit to stop the operating means.

7. In a crossing signal arm apparatus, in combinatio-n, a horizontallypivoted signal roadway arm, a horizontally pivoted signal sidewalk arm,motor driven means for operating said arms through a resilient drivingconnection, and means connected to one of said arms operable upon theinterposition of a force opposing movement of the same arm by saidoperating means acting through said connection for stopping theoperation of both arms.

8. In a crossing signal arm apparatus, in combination, horizontallypivoted roadway and side- Walk arms, motor driven means for operatingsaid arms through a resilient driving connection, and means operated bya force opposing the movement of either' arm by said operating meansthrough a resilient driving connection for stopping the operation ofboth arms.

9. In a crossing signal arm apparatus, in combination, a horizontallypivoted signal motor driven means for operating said arm including aresilient driving connection to said arm, said connection permittingrelative movement of the arm and operating means, and means actuated bya predetermined movement of the arm relative to the operating means whenthe latter is stationary for closing a circuit to the motor to start theoperating means.

10. In a crossing signal arm apparatus, in combination, a horizontallypivoted signal arm, motor driven means for operating said arm includinga driving connection yieldably engaged with said arm, said connectionnormally holding said arm and driving means resiliently in asubstantially immovable relative relation, said connection permittingrelative movement of the arm andoperating means, means actuated by apredetermined relative movement of the arm and operating meansoccasioned by a force exerted on the arm opposing its movement by theoperating means for stopping the operating means, and means actuated bya further relative movement of the arm and operating means in the samedirection for starting the operating means.

.1.1. In combination, a crossing signal arm pivoted horizontally, avertically disposed stationary housing, a support for said armconstructed for rotation relative to said housing to provide movement ofthe arm about the vertical axis, means for driving said arm mounted forrotation With said support, and means permitting rapid deflection of thearm approximately 90 from its normal position parallel to the railwayand for returning it to said position, a cam carried by said support,and a dash pot and plunger therein constructed to follow said cam topermit rapid deflection of said arm and for causingv the arm to returnslowly to normal position and to yieldably lock the same thereat.

12. In combination, a crossing signal arm pivoted horizontally, avertically disposed stationary housing, a support for said armconstructed for rotation relative to said housing to provide movement ofthe arm about the vertical axis, means for driving said arm mounted forrotation with said support, and means permitting rapid deiiection of thearm approximately 90 from its normal position parallel to the railwayand for returning it'to said position, a cam carried by said support,and a dash pot and plunger therein constructed to follow said cam topermit rapid deiiection ci said arm and for causing the arm to returnslowly to normal position and to yieldably lock the same thereat againstdeflection by any force less than a predetermined force.

13. In a crossing signal apparatus, having a signal arm, a reversiblemotor for raising and lowering said arm, a gate control circuitconnected to said motor including a single relay normally held energizedWhile the arm is up, the release of which Will cause the motor' to lowerthe arm and the energizing of which will cause the motor to raise thearm, and means for stopping the motor during the raising of the armactuated by a predetermined downward pressure against said arm beforethe latter has reached fully raised position.

.JAMES W.' JENKINS.

CERTIFICATE or Gonnnorion.

Patent No. 1,934,429. November 7, 1933.

' JAMES w. sentirne.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correetion as oilows: Page iti,line 20, claim 8, for "through a resilient driving" read acting throughsaid; and iine 35, claim it), for "yieldabiy" read resiliently; and thatthe said Letters Patent should be read with these corrections thereinthat the same may conform to the record oi the case in the PatentOffice. f

Signed and sealed this 12th day of December, A. D. 1933.

M. Hopkins (Seal) Acting Commissionei oi Patenti.

